Means for preventing sparking in electrical devices.



L. GRUBMAN. v MEANS FOR PREVENTING SPARKING IN ELECTRICAL DEVICES.

APPLICATION FILED APR. 16, 1912.

Patented Aug. 18, 191 1 2 SHEETS-SHEET 1.

III

HIHI

III!!! III! INVENTUR Grobman ATTORNEYS L. GRUBMAN. 8 FOR PREVENTING SPARKING IN ELECTRICAL DEVICES.

MEAN 1,107,932.

APPLICATION FILED APR.16, 1912,

Patented Aug. 18, 191 i 2 SHEETS-BHEET 2.

IIIIIT IIIIII R 8 w m n U n I. v. a N a M l h m 0 /I M m w 11]! m I G nx E o M x I u l I 4 jfl' I' C O L WITNESSES LEO GRUIBMAN, OF NEW YORK, N. Y.

MEANS FOR PREVENTING SPARRING IN ELECTRICAL DEVICES.

To all whom it may concern Be it known that I, LEO GRUBMAN, a citizen of the United States, and a resident of the city of New York, borough of the Bronx, in the county and State of New York, have invented a new and Improved Means for Preventing Sparking in Electrical Devices, of which the following is a full, clear, and exact description.

The principal object of my invention is to provide a new and improved core in electromagnetic devices, together with suitable means for varying the flow of the current, as to direction and amount, whereby the field may be reversed or controlled.

A further object of my invention is to provide new and improved windings for cores of electromagnetic devices which, together with suitable cooperating parts, control the flow of currents through such windings, in order to regulate the magnetic field produced thereby, so that parts of various devices may be moved or caused to perform mechanical work through variation of such field, the result being obtained without sparking.

A still further object of my invention is to provide the core of an electro-niagnetic device with a number of windings so connected together, and cooperating with suitable devices, that the magnetic field set up by such winding may be reversed, or may be regulated to such an extent that mechanical work may .be done by certain elements through the influence of the field due to such windings, the construction and arrangement of parts providing such regulation, marked by the absence of opening the circuit contain ing the said windings, whereby sparking is avoided.

Other objects and advantages of the invention, not particularly set forth at this time, will appear as the description thereof proceeds, it being noted that-the parts set forth and described in the drawings are merely typical and illustrative of what may be used to accomplish the purpose of the invention, such parts being capable of various changes in design and relation among themselves.

My invention is of general application in various arts associated with the general dis tribution of electric currents, typical instances being in electric motors of various kinds, positive-break intcrrupters used with Specification. of Letters Patent.

Application filed April 16, 1912.

Patented Aug. 18, 1914. Serial No. 691,187.

.Ruhmkorfi' coils, various types of apparatus employed in connection with wireless transmission stations, and motor controlled Klaxon horns.

Reference is to be had to the accon'ipanymg drawings, forming a part of this specification, in which similar characters of reference denote corresponding parts in all the views, and in which Figure l is a diagrammatic arrangement of a. core having a number of windings thereon, together with mechanically-driven means for changing the relative directions of flow of the current through the windings; Fig. 2 is a similar view, the mechanicallvdriven means being shown in another posi tion: Fig. 3 is a diagrammatic view showing a different structure for controlling the directions of the currents through the windings; Fig. 4 is a similar view showing such structures in another position. y

In order to set forth one method of performing the invention, Figs. 1 and 2 will be explained. Let any suitable core have the windings w, m m and as placed thereon, the core and windings being merely typical and setting forth the well-accepted construction of obtaining a magnetic field. when desired. Let a, b, c, and (5 represent a succession of electrically-independent sectors; these sectors are preferably held stationary, it being noted that the sector a has a lead a connected thereto, while the sector I) has a lead 2 connected thereto, there being a lead ;0 extending from the sector 0, and a lead 8 extending from the sector d. Adjacent the sectors, and adapted to make contact with opposite ones, are the brushes 6, f, suitably mounted in position on an arm 13 mounted at one end of the shaft 10 which has a pulley 11 thereon; any suitable sort of belt 12, or equivalent device, engages the pulley so that turning of the shaft will bring the brushes 6, f, alternately into contact with the sectors a, c, and b, d. Mounted on the shaft 10 are the collector rings 6, f, the ring 6' being in electrical circuit with the brush a, and the ring being in electrical circuit with the brush f; resting on the ring 6 is a brush 9, and on the ring f is the brush h, these brushes forming means for leading current from any suitable source of supply to the brushes 4: and f, whence the paths of the sparking Current through the windings will follow. 110

The lead a from the sector a is connected to one end of the winding :0 through the lead Z, the lead 70 extending from the junction j, being connected to one end of the winding :0 the lead p, extending from the sector 0, is connected to one end of the winding 00 through the lead a, the lead m, extending from the junction 0 being connected to one end of the winding 02*,- adjacent ends of the windings a2 and m are connected at 'v, whence a lead 2 is led to the sector b. Adjacent ends of the windings :2 m are brought together at w, whence a lead 8 extends to the sector d. It will be noted that the direction of the windings on the core is the same throughout the extent of the windings. Suppose, now, that current is led into the windings through the brushes 9 and 71; the brush 6, which is in electrical contact. with the sector a, is, we will say, the positive side of the line, the brush 9 being therefore positive and the brush in negative. The current. passes through the lead 6 to the point y, whence it divides, part going to the lead Z, thence through the winding m and also through the winding 00, to the point 0, whence it flows to the lead p, to the sector 0 connected to the negative side of the line,

*through the brushes 7 and It, at the point j,

the other portion of the current passes through the lead 70, thence through the windings no and 00 leaving the winding m through the lead m, whence it joins the .re turn lead 79 at the point 0. It will be noted that the windings a2 and 00 are in series with each other and that the windings 00 and 00* are also in series with each other, each pair of windings, however, being in multiple with the source of supply. Since the brushes e and f are not in contact with the sectors 6 and (Z, the current cannot. return through the leads 8 and z. The direction of the flow of the currents through the windings is the same, whence the resultantmagnetic field set up within and about the core X. Suppose, now, that the brushes 6 and f are brought into contact with the sectors 6 and (Z by turning the shaft 10, the paths of the currents will then be as follows: The brush 6 is positive, as before, the current now passing through the lead 2 to the point r, whence it divides, part passing through the winding 02 and part through the winding m the portion passing through the Winding to leaving that winding through the lead 97. and then passing from the point 0 to the lead me, and thence through the winding m to the point to, whence it returns to the sector cZ through the lead 8; at the point a, the current divided, the other portion passing through the winding m thence through the lead Z to the point 7', thence through the lead 7a to the winding m, to the point w, where itjoins the current passing through the windings first described, and thence to the other side of the circuit.

It will be noted that, since the brushes 0 and are not in contact with the sectors a and c, the current can not traverse the leads 2' nor 7). In this second position oi the brushes it will be noted that the direction of the currents in the windings a? and m are the same, while the direction oi the currents in the windings a, are also the same, the directions, however, in one pair of windings being the opposite of the directions in the other pair; hence the magnetic field set up by the four windings, as described in connection with. 'Fig. l, is materially weakened, due to the reversal of the direction of the how oi" current in some of the windings, these windings being capable of adjustment in various ways so that the resultant field may be zero, as indicated in Fig. 1, or may be of maximum strength, as desired. Hence any moving parts, set in motion or actuated by the magnetic field due to these windings, may be controlled through this variation of the fiow of the currents; it may be desirable in some instances that, if the windings as shown in Fig. l are to result in a north pole at the upper end of the core, at any moment such polarity should be reversed or destroyed, the windings being capable of design in order to etlect this, as set forth in the outline of Fig. 2. It will be noted now that the brushes 6 and 7, when passing from the sectors (a and 0 into contact with the sectors 1) and (Z do not open the electric circuit at any time, since these brushes, during a portion of their travel, bridge the insulation between the sectors, the brush 6 being in contact with the sectors 0., Z), while the brush is in contact with the sectors 0, (Z. It will. be noted further that, ii the arm 13 carrying the brushes 6 and f is brought into contact with the sectors 0 and (Z, the currents in the windings on the core will be in the same direction, the direction, however, being the op posite to that shown in Fig. 1, the resultant eficct, however, being the same since the magnetic field is then due to the current [lowing through all the windings. After the brushes pass from the sectors 0 and a and again come into contact with the sectors (Z and Z). the parts will appear as shown in Fig. 2, since the direction of the currents in some of the windings is reversed.

Of course, in the operation of devices or constructions en'ibodying the invention herein disclosed and claimed, the variation in the directions of the currents takes place very rapidly, it being hcrne in mind, however, that once the electric circuit closed through. the brushes g, it, such circuit is not again opened during the operation of the outfit. \Vhereas in Fig, 1 the windings as and m were in series, and the windings x it were also in series, the parts, however, being in multiple, it will be noted that in Fig. 2 the windings m and are in series and the windings .21 and a? are in series, the parts, however, being in multiple. N ow it is obvious that by adding windings having different numbers 01' eonvolutions, as well as by properly apportioning the resistances of the diil'erent windings, it is merely a matter of mechanical skill to provide for any desired strength of magnetic field. That is, the range of strength of the field may vary from a maximum to zero.

In Figs. 3 and 4, a different construction for effecting the changes in the flow of the currents through the windings is set forth, the inventive idea involved, however, being identical with that shown in Figs. 1 and 2. In this case, let a, b, 0, (Z represent fixed contacts or terminals, while 6 6 represent spring arms connected. to one side of the circuit 9', f and f designate other spring arms connected to the other side h of the circuit. One position of the arms is shown in Fig. 3; in such position the arm 6 is in contact with the terminal a and the arm f is in contact with the contact 0, it being noted that the arm e is out of contact with the terminal f and that the arm f is out of contact with the terminal d. Assuming now that the current enters through the lead 9, it will pass through the arm 6 through the terminal a, through the lead 2' to the point j, whence it will divide; the other side of the circuit extends from the lead It through the terminal 0 to the point 0; the resultant state of aiiairs, due to such paths of the currents, is similar to that shown in Fig. 1; suppose, now, that the arms 6-, c and 7", f" are moved upwardly in order to bring the arms 0 into contact with the terminal f and the arm f into contact with the terminal d, the arrangement of the parts being then as represented in Fig. t; the currents now divide through the wind ings 0/, :6 0/1 (11*, as shown in this figure, the resultant etl ect being similar to that shown in Fig. 2; it is to be borne in mind that in this construction the arrangement of the arms with respct to each other is such that 0 comes into engagement with before (2 leaves engagement with a. and that f engages cl before f leaves 0. This method of operation is similar to the passage of the brushes 6, f, oi? Figs. 1 and 2, from one pair of sectors to the next pair, the brushes bridging the insulation between the sectors and momentarily sending current through adjacent ones. I do not limit myself, however, to the exact means here shown for actuating the resilient arms-c c, as various other expedients may be employed for this purpose.

It is clear that, the method of winding having been disclosed and the relation of the currents among themselves, together with the resultant eli'ects, having been determined, various mechanical devices actuated in divers ways may be employed to effect such relations of the currents through the different windings without departing from the inventive idea disclosed.

Having thus described my invention, I claim as new, and desire to secure by Letters Iatent:

1. The combination of a core of magnetic material with a number of windings thereon, together with means for changing the direction of flow of the current through some of the windings, the said means being also adapted to reverse the flow of the current through all of the windings.

:2. In combination with a source of supply. an electromagnet comprising a number of windings connected in multiple with the said source of supply, each of the windings so connected in multiple consisting of a plurality of individual windings, and means 'for changing the direction of flow of the current through one of the windings in each of the said groups, the said means being also adapted to reverse the current through all of the windings.

3. The combination with a source of sup ply, of an electromagnet embodying a plurality of windings, the said windings, during operation of the elcctromagnet, being divided into two groups, together with means for changing the direction of flow of the current through one of the windings in each group. the said means being also adapted to reverse the direction of the current through both groups.

4-. .In combination with a source of supply, an clectromagnet comprising a plurality of windings, means between the said source of supply and the windings. whereby the direction of current through all of the windings may be the same, the said means being adapted to change the direction of the flow through some ol the windings, the said means being further adapted to reverse the direction of flow through all of the windings.

5. In combination with a source of supply, means for producing a magnetic field comprising a plurality of windings, with a mass of magnetic material adjacent the windings, and means in circuit with the said source of su 'iply and connected to the said windings, whereby the direction of flow of the current through all of the windings may be such as to provide a field of maximum strength, the said means being adapted to weaken the said field by reversing the direction of [low through some of the windings, further operation of the said means strengthening the field, the polarities being reversed.

6. in combination with a source of supply, a mass of magnetic material having a numher of \VllltlillfS thereon, means between the source of supply ancl the windings, whereby the dirertion of current through the Winding; is the same in all of them, thereby producing a field of given polarity and maximum strength, the said means being adapted to change the direction of low of the current through some of the windings in order to weaken the said field, the said means being further operable to strengthen the field and 10 with a reverse polarity.

In testimony whereofI have signed my name to this specification in the presence of two subscribing Witnesses.

LEO GRUBMAN.

Vitnesses &

PHILIP D. ROLLHAUS,

LAURENCE J. GALLAGHER. 

